The following two U.S. patent applications describe the use of fiberoptic luminaires that may be used for lighting refrigerated or other types of cases for displaying food or other contents: U.S. patent application Ser. No. 11/379,997 filed Apr. 24, 2006 for Lighted Refrigerated Display Case with Remote Light Source by Roger Buelow et al., and U.S. patent application Ser. No. 11/379,999 filed 24 Apr. 2006 for Lighted Display Case with Remote Light Source by Roger Buelow et al. The foregoing applications have some common inventors with the present application, and they are assigned to the same joint owners as the present application: the joint owners are Fiberstars, Inc. and Optical Research Associates. The entireties of the disclosures of the foregoing applications are hereby incorporated by reference.
The foregoing U.S. patent applications disclose fiberoptic luminaires with extractor patterns for extracting light from the side of the luminaires. The extractor patterns may comprise light-scattering particles or a textured pattern on the surface of a luminaires by way of example. As used herein, “fiberoptic luminaire” includes an acrylic rod luminaire that receives light directly from a light source as well as indirectly through a fiberoptic cable or other structure. Typically, the foregoing paint or textured-pattern surfaces comprise a scattering-type extractor pattern, as opposed to a specular-type extractor pattern.
As used herein, an extractor pattern, of either the scattering or specular type, produces a continuous swath of light on a target area.
As used herein, some extractor patterns are categorized as “scattering” extractor patterns and others are categorized as “specular” extractor patterns. These terms are in more detail below in the detailed description below. Generally, a scattering extractor pattern for light on an elongated luminaire tends to provide light onto a target area, along the length of the luminaires with a moderate degree of directional control over the light in the length direction. In the direction orthogonal to the length, the scattering extractor pattern density and the cross sectional shape of the elongated luminaire provide a smooth target distribution that is free of localized spatial structure but still provides good directional control. Scattering extractor patterns are relativity insensitive to fabrication errors.
In contrast, a specular extractor pattern can provide light along the length of a luminaire with more localized control than can a scattering extractor pattern.
Sometimes, it would be desired to not only utilize a scattering extractor pattern on a luminaire but also be able to exert a higher degree of longitudinal directional control over some of the light emitted by the luminaires. In some cases, this longitudinal directional control can provide more localized control over the target distribution, thereby enabling improved uniformity and a reduction in the fraction of light that spills outside of the target area.